Polish composer of mostly orchestral, chamber, choral, vocal, and piano works that have been performed throughout the world.

Prof. Borkowski studied composition with Kazimierz Sikorski and piano with Jan Ekier and Natalia Hornowska at the Fryderyk Chopin University of Music in Warsaw from 1959–65, where he earned his MA in both subjects. He also studied musicology with Józef Michał Chomiński at the University of Warsaw from 1959–66 and there earned his MA, then studied composition with Nadia Boulanger and Olivier Messiaen at the Conservatoire National Supérieur de Musique de Paris from 1966–68 and musicology with Barry S. Brook and Jacques Chailley at the Université Paris Sorbonne-Paris IV from 1966–68, both on a grant from the government of France. He later attended the Ferienkurse in Darmstadt in 1972 and 1974, as well as courses with Franco Donatoni at the Accademia Musicale Chigiana in Siena in 1973 and 1975, where he earned a Diploma di Merito, and with Iannis Xenakis at the École des Hautes Études en Sciences Sociales in Paris.

Among his honours are Second Prize in a competition for young composers in Warsaw (1966, for Dram), a prize in the competition G. B. Viotti in Vercelli (1969, for Toccata) and Third Prize in the competition Karol Szymanowski in Warsaw (1974, for Acclamations). He has also received the Award of the Minister of Culture and National Heritage (1976, 1980, 1982), the Silver Cross of Merit from the government of Poland (1977), Silver Medal in the Premio Vittorio Gui in Florence (1979), and the Medal of the Fryderyk Chopin University of Music (1981). He has also earned two classes of the Order of Polonia Restituta (Cross of the Knight, 1984; Cross of the Commander, 2002) and First Prize in the International New Music Competition in New York, New York (1990, for Pax in terra II).

Prof. Borkowski is also active in other positions. As a pianist, he was primarily active from the 1950s–60s, playing his own works and music by 20th-century composers in Austria, Canada, France, Italy, Poland, Russia, and the USA. He served as deputy chair of the chapter of the Związek Kompozytorów Polskich – Polish Composers Union in Warsaw from 1971–77. He later founded the Festival of the Laboratory of Contemporary Music Society in Warsaw in 1985 and has served as its artistic director since 1985. In addition, he has served as president of the Laboratory of Contemporary Music Society since 1995.

He has taught composition and orchestration at the Fryderyk Chopin University of Music since 1968, where he has been a full professor since 1989, chair of the department of music theory since 1993 and dean of the faculty of composition, conducting and music theory since 1996. He previously served there as vice-president from 1978–81 and 1987–90. He has organised its postgraduate courses in music theory since 1998 and in composition since 2000. In addition, he has taught as a visiting professor at universities in Canada, France, Italy, South Korea, and the USA.